Selenide Vibrations...

In this illustration, an infrared laser beam (orange) triggers atomic vibrations in a thin layer of iron selenide, which are then recorded by ultrafast X-ray laser pulses (white) to create an ultrafast movie. The motion of the selenium atoms (red) changes the energy of the electron orbitals of the iron atoms (blue). (Courtesy: Greg Stewart/SLAC National Accelerator Laboratory)

Topics: Condensed Matter Physics, Materials Science, Solid State Physics, Superconductors

Two important breakthroughs in the understanding of iron-selenide superconductors have been made by two independent research groups. One team has shown that the electrons responsible for superconductivity in the material probably come from a specific atomic orbital. The other team, meanwhile, has measured the interaction between electrons and atomic vibrations in iron selenide, which is believed to be involved in its superconductivity.

The research could shed light on the mystery of why some materials based on iron selenide are superconductors at relatively high temperatures, which has puzzled physicists for more than a decade. While bulk iron selenide is a superconductor below 8.5K, this transition temperature can reach as high as 75K when an ultrathin trilayer of the material is grown on certain substrates.

Experiments shed new light on iron superconductors, Hamish Johnston, Physics World